This invention relates to a turbo-charged engine and more particularly to an improved manifolding system for delivering exhaust gases from the combustion chambers to the turbine stage of the turbo-charger.
The use of turbo-chargers for internal combustion engines is well known. A turbo-charger has the advantage in that it is driven by the exhaust gases of the engine and thus reclaims energy which might be otherwise lost. However, one of the disadvantages of a turbo-charger is the so-called "turbo lag" that results from the fact that the exhaust pressure does not increase as rapidly as the load on the engine under acceleration conditions.
In order to reduce turbo lag, a wide variety of devices and methods have been employed. Specifically, it is known that the positioning of the turbine stage inlet as close as possible to the exhaust ports of the engine will have the result of reducing turbo lag. However, by placing the turbine stage in direct communication with the exhaust port and close to it, some of the advantages of exhaust port tuning are lost and power can be deteriorated under some running conditions. In addition, if the exhaust passage is short and the turbine stage of the turbo-charger is mounted directly to the engine, primarily the cylinder head where the exhaust port is normally formed, the heat from the turbine stage can be transmitted to the engine and cause loss of performance and/or possible deformation of the engine components. Also, when multiple cylinders are employed, it is desirable to operate the turbo-charger in such a way that the individual exhaust passages will have substantially the same length and equal flow from them to the turbine stage.
It is, therefore, a principal object of the invention to provide an improved, turbo-charged internal combustion engine.
It is a further object of this invention to provide a construction for turbo-charging an engine wherein optimum length exhaust passages can be employed without introducing turbo lag and without unduly heating the cylinder head of the engine.
It is a yet further object of this invention to provide an improved arrangement for operating a turbo-charger from an internal combustion engine with minimum lag and minimum heat distortion for the cylinder head.